The Prime Minister rejected suggestions of a second referendum, negotiating a different type of Brexit, or an extension of the Article 50 withdrawal process to end the impasse over the deal agreed with Brussels on Sunday.
But the scale of opposition to the deal appeared to grow, as loyalist Tory Sir Michael Fallon described the deal as a “huge gamble” and Labour MP Caroline Flint, who has previously said she could back a deal, called for a rethink to bridge divides.
With around 80 Tory MPs lining up to oppose the deal alongside the DUP and Labour, Don Valley MP Ms Flint noted that both Mrs May and Jeremy Corbyn had made clear their priorities are to avoid a no deal Brexit.
She urged them to hold talks “in the national interest” on a deal both sides can back which protects workers’ rights and secures a “sustainable” customs policy.
Sir Michael meanwhile questioned the vagueness of the political declaration on future EU-UK relations which accompanies the withdrawal agreement, which commits Brussels to using “best endeavours” to ensure a good trade deal is struck.
He warned: “Are we not... being asked to take a huge gamble here?
“Paying, leaving, surrendering our vote and our veto without any firm commitment to frictionless trade or the absolute right to dismantle external tariffs.
“Is it really wise to trust the future of our economy to a pledge simply to use best endeavours?”
In her statement, however, Mrs May insisted her deal “delivers for the British people” and warned that rejecting it would lead to division and uncertainty.
She was loudly barracked by MPs as she insisted that no better deal was available.
The PM also made clear she would go over the heads of MPs and appeal directly to voters for their backing, telling MPs: “Our duty as a Parliament over these coming weeks is to examine this deal in detail, to debate it respectfully, to listen to our constituents and decide what is in our national interest.”
Later, she rejected various calls for a second referendum, and said: “I’m clear that we will not extend Article 50.”
A Number 10 source said Mrs May was confident of winning the vote on the Brexit deal despite the scale of opposition.
But she was warned by Brexiteer Tory Mark Francois that her deal will “never get through”, while his Remainer colleague Anna Soubry also said the majority of MPs “will not vote in favour of the Prime Minister’s deal, despite her very best efforts”.
“So she needs plan B, “she said.
PM admits using wrong language about EU nationals
Theresa May has said she used the wrong language when she told business leaders her post-Brexit immigration plans would stop EU workers being able to “jump the queue”.
The Prime Minister was heavily criticised for the remarks, made in a keynote speech to the CBI’s conference in London last week, where she outlined plans to curb immigration after Brexit.
Mrs May told MPs she should “not have used that language” when she was asked about the speech by the SNP’s Philippa Whitford, whose husband is German.
Ms Whitford said the PM’s comments had managed to “insult and upset” EU citizens who live in the UK.